Little is known about the results of young vascular neurosurgeons who perform only microsurgical clip reconstruction in the era since the International Subarachnoid Aneurysm Trial (ISAT) or about the training and caseload required to equivocate the results of senior, more experienced colleagues. The aim of this study was to compare clinical outcomes of patients treated by young and senior vascular neurosurgeons at Erasmus MC University Medical Center Rotterdam, adjusting for case mix. A partially prospective and partially retrospective database was used. Hierarchical mixed models with a random intercept for surgeon were used for confounder adjustment, and propensity score matching for complexity was used to create comparable groups. The study included 609 patients harboring 767 aneurysms. Most (86%) of the aneurysms had at least 1 complexity characteristic, with the majority having 3 characteristics. The most often encountered complexity characteristics were the presence of a broad neck and the presence of branches emerging from the aneurysm. Use of temporary clipping and skull base approaches was significantly higher in the young vascular neurosurgeons group (P < 0.0001). The complexity score differed significantly between senior and young vascular neurosurgeons (P < 0.001). After propensity score matching for complexity, multivariable logistic regression showed young vascular neurosurgeons to be significantly associated with better outcomes for ruptured aneurysms (propensity score weighted odds ratio 0.55 [95% confidence interval 0.35-0.88], P= 0.01). In a high-volume neurovascular center where both endovascular and microsurgical treatment options are available, young vascular neurosurgeons can be trained to achieve at least the same results as their senior colleagues despite increased complexity.